1. Field of the Invention
This invention relates to photosensitive materials for the formation of relief images, printing plates and photographic reproductions, and in particular, to photosensitive materials comprising photosensitive high molecular weight compounds which have a .beta.-thienylacrylic acid ester or amide group as a functional group.
This invention also relates to monomers which can be polymerized to form these photosensitive high molecular weight compounds.
2. Description of the Prior ARt
Heretofore, many studies have been made on systems which undergo changes in solubility, adhesiveness, hardness or the like at the areas irradiated with light, particle rays or electromagnetic waves, and some of them are presently being used to prepare lithographic printing plates, stencils, photoresists, photohardenable paints and similar photomechanical images.
In the prior art, much research has been conducted on light sensitive compounds such as .alpha., .beta.-unsaturated carboxylic acid derivatives and .alpha., .beta.-unsaturated carbonyl compounds (for example, (1) J. Kosar, Light Sensitive Systems, John Wiley & Sons, New York, 1965, Chap. IV; (2) A. Schonberg, Preparative Organic Photochemistry, Springer-Verlag, New York, 1968, Chap. 8). In particular, the photoaddition four-membered ring-forming reaction of cinnamic acid derivatives has been studied extensively among the unsaturated carboxylic acids (for example, (3) P. Silber, Ber. dtsch. Chem. Ges., 35, 4128 (1902)) and, furthermore, the application of high molecular weight compounds having cinnamic acid ester groups to a lightsensitive system has also been well studied (for example, Silber, ibid., U.S. Pat. Nos. 2,835,656; 3,357,831; 3,737,319; 3,418,295; 3,647,470; 3,409,593; 2,956,878; 3,173,787; 3,023,100; 3,066,117; 3,748,144 and 3,756,820 and British Pat. No. 695,197). In these studies, however, functional group containing polymers having sufficient sensitivity using commercially available, simple structures and simple procedures have not yet been obtained.
An object of the present invention is to provide a photosensitive system in which the disadvantages of prior art systems, especially with respect to sensitivity, have been overcome.